Passive House Principles Meet Thermal Mass Storage
Combining passive house design with underground thermal storage creates homes that are nearly energy-independent — here is how it works.
Gabriel Tremblay
GeoMass Team
Passive house design minimizes energy demand through superior insulation, airtight construction, and heat recovery ventilation. When you add underground thermal mass storage to a passive house, you create a system that can operate with minimal external energy input.
Key Principles
A passive house reduces heating demand by up to 90% compared to conventional construction. Adding GeoMass thermal storage takes this further by smoothing out the remaining demand across seasons.
The Integration
The thermal storage system connects to the home's mechanical room and interfaces with the heat recovery ventilator (HRV). During mild weather, excess solar gain is directed underground rather than being vented away.
Case Study: The Prairie Thermal
Our Prairie Thermal model was designed from the ground up with these principles. In its first winter, it consumed 78% less heating energy than a comparable conventional home.